Formication: What Causes Crawling Ant Sensation in Arms & Legs?

Abnormal skin sensations are very annoying. It is even more annoying, when you are unable to explain it. One such skin sensation that feels like ants or insects crawling on your arms and legs, underneath the skin is known as Formication.

While many people have itching of the skin, formication is a rare condition that very few people may have. Coming from the Latin word “formica” which means ants, Formication indicates that type of paresthesias or skin sensation that has symptoms such as –

• Crawling of ants in the legs and arms
• Tingling sensation
• Prickling of pins and needles in the arms and legs
• Burning sensation
• Itchiness.

What causes serious trouble apart from the weird and annoying sensation, is that people start scratching their skin vigorously, when they suffer from Formication. As a consequence, they cause serious damage to the skin.

Formication or the sensation of ants and other insects or sometimes even the sensation of reptiles crawling on the arms and legs, underneath the skin, is considered to be a tactile hallucination. It is believed to be a side effect of several disorders. So, its major reasons include –

Often Formication is associated with drugs and substance abuse and psychotic states. Those, who have been dependent on alcohol and other substances such as crystal meth, amphetamines, cocaine or heroin, suffer from Formication after a long term dependency on these substances. In fact, withdrawal from these substances and drugs can also lead to this condition.

Not just the substance, alcohol or drugs, sometimes the prescribed medicines are also a reason behind Formication. Adderall, Ritalin, Wellbutrin and Lunesta are some of the medicines that cause Formication sensations, even though they are prescribed medicines. Here, must be mentioned that these medicines are meant for psychological problems, diseases and disorders. Lunesta is prescribed to treat insomnia, Ritalin is prescribed to treat ADHD or attention deficit hyperactivity disorder. Wellbutrin, on the other hand, is prescribed to people who want to quit smoking or are suffering from depression.

Those, who are intoxicated or are delirious and undergoing treatments for these with prescription medicines mentioned as above, are often seen to scratch themselves due to Formication sensations. This leads to ulcers and gouged out pits especially in areas that are easily accessible such as arms, legs, thighs and sometimes even the face or scalp. However, it can well be reported that Formication is a delusional form of parasitosis in which the sufferer only has a delusion of bugs crawling on their legs and arms, or rather the entire body. Since it is a form of psychosis, people are often skeptical and suspicious about their treatment procedure. They are hostile towards the treatment provider, not believing in the competence of the treatment.

There are some other diseases as well that can lead to the Formication sensations. These would include syphilis, herpes zoster or shingles, diabetic neuropathy, Lyme disease, skin cancer and Parkinson’s disease etc. Sometimes, fibromyalgia is also a cause behind formication. Since in fibromyalgia, the brain doesn’t interpret or process the signals or sensations properly, a tingling, itching and crawling sensation is often experienced by many.

A percentage of the Formication patients are women who have had their menopause. Though it can’t be said that menopause is a cause behind Formication, as menopause makes the skin dry and itchy, women may feel the sensation of ants or insects crawling on their arms and legs. However, the feeling is essentially psychological.

If you are experiencing any such feeling or sensation in the arms, legs or any other body part for that matter, it is always important that you see a doctor. The doctor will be able to tell you, the exact cause of formication – whether it is a result of any other hidden disease or disorder.

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